Motor vehicle axle with subframe

ABSTRACT

A motor vehicle axle includes a subframe which has a bushing for linkage to a vehicle body. The bushing defines an axis and includes a bushing body and a face plate which is welded to the bushing body via a weld seam and has a contact surface which is raised in relation to the weld seam, as viewed in a direction of the axis.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the priority of German Patent Application,Serial No. 10 2013 106 001.3, filed Jun. 10, 2013, pursuant to 35 U.S.C.119(a)-(d), the disclosure of which is incorporated herein by referencein its entirety as if fully set forth herein.

BACKGROUND OF THE INVENTION

The present invention relates to a motor vehicle axle with a subframefor linkage to a vehicle body.

The following discussion of related art is provided to assist the readerin understanding the advantages of the invention, and is not to beconstrued as an admission that this related art is prior art to thisinvention.

Motor vehicle axles are known in the art having a subframe for linkageto a vehicle body, with control arms, wheels and/or shock absorbersbeing connected to the subframe to produce the chassis. The subframetypically has connecting crossbeams which extend underneath the motorvehicle floor. Connected to the crossbeams are frame components forcontrol arms and/or mounts for attachment of the subframe to the vehiclebody. In view of the loads to be expected and in particular because ofthe influence of gravity upon the vehicle body, the chassis rests uponthe subframe.

It would be desirable and advantageous to provide an improved motorvehicle axle with subframe to obviate prior art shortcomings and toconstruct it so as to be easy and cost-effectively to produce and to bereliable in operation.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a motor vehicle axleincludes a subframe having a bushing for linkage to a vehicle body, thebushing defining an axis and including a bushing body and a face platewhich is welded to the bushing body via a weld seam and has a contactsurface which is raised in relation to the weld seam, as viewed in adirection of the axis.

In accordance with the present invention, it is now possible to firstproduce the bushing body, using conventional tube manufacturingprocesses. The bushing body may also be implemented as an extruded partor impact extrusion part. Thus, the bushing body may be configured ofany individually selected length in a simple and cost-effective manner.An attachment onto the vehicle body can be implemented by welding theface plate as welded part onto the bushing body of selected length.Welding involves in particular spot welding or provision of a continuouscircumferential weld seam. In relation to the vertical direction, thecontact surface of the face plate is positioned at a distance above theweld seam. In this way, the face plate is not adversely affected interms of geometric precision and thus prevented from uneven contact uponthe vehicle body, despite changes in the surface characteristics causedby the welding process, for example as a result of material melting oradded filler material. Thus, the bushings can be produced at highreproducibility and connected to the subframe so that motor vehicleaxles can be manufactured with such a subframe at high precision withrespect to attachment points of the vehicle body.

According to another advantageous feature of the present invention, thebushing body can be configured in the form of a tube. The cross sectiontube can thus be best suited to the demanded space dimensions at handand/or to the stress to be expected. It is therefore possible to producenot only round tubes as bushing body that is then provided with a faceplate, but the tubes may have an angular cross section, e.g. polygonalcross section, or oval cross section. Of course, combinations of theafore-mentioned cross sections are conceivable as well in order toconform the bushing body to the installation situation in the subframeand/or to the stress to be expected.

According to another advantageous feature of the present invention, thetube may be longitudinally welded and/or clinched and/or roll formedand/or extruded. Both the tube and the face plate may be made of metal,e.g. steel material or light metal material.

According to another advantageous feature of the present invention, theface plate can have a depression, thereby forming the contact surfacefor attachment to the vehicle body. Thus, the face plate is configuredas formed part which is shaped in such a way as to produce a contactsurface which is raised vertically upwards in relation to the ends ofthe face plate in the later installation situation, with the ends of theface plate, in turn, being welded to the bushing body. This ensures adistance between the weld seam or flanged seam and the contact surface,thereby ensuring high geometric precision of the subframe while at thesame time guaranteeing reproducibility.

According to another advantageous feature of the present invention, theface plate can have a U-shaped cross section and defines a bottom platewhich forms the contact surface, and legs which extend from the bottomplate and are welded to the bushing body. Advantageously, the U-shapedface plate is configured as a pot.

According to another aspect of the present invention, a method includeswelding ends of legs of a face plate to confronting ends of a tubularbody along a weld seam, such that a contact surface of the face plate israised in relation to the weld seam, as viewed in an axial direction,thereby producing a bushing for linkage of a subframe for a motorvehicle axle to a vehicle body.

According to another advantageous feature of the present invention, abottom of the face plate between the legs can be recessed outwards toform the contact surface.

BRIEF DESCRIPTION OF THE DRAWING

Other features and advantages of the present invention will be morereadily apparent upon reading the following description of currentlypreferred exemplified embodiments of the invention with reference to theaccompanying drawing, in which:

FIG. 1 is a top perspective view of a subframe according to the presentinvention for manufacture of a motor vehicle axle;

FIG. 2 is an enlarged detailed perspective view of the area encircled inFIG. 1, depicting a bushing on the subframe;

FIG. 3 is a top perspective view of the bushing;

FIG. 4 a is a cross sectional view of one embodiment of a bushingaccording to the present invention for attachment to a vehicle body;

FIG. 4 b is a cross sectional view of another embodiment of a bushingaccording to the present invention for attachment to the vehicle body;

FIG. 5 a is a schematic illustration of a bushing as a pressed part; and

FIG. 5 b is a schematic illustration of a bushing as a flanged part.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Throughout all the figures, same or corresponding elements may generallybe indicated by same reference numerals. These depicted embodiments areto be understood as illustrative of the invention and not as limiting inany way. It should also be understood that the figures are notnecessarily to scale and that the embodiments are sometimes illustratedby graphic symbols, phantom lines, diagrammatic representations andfragmentary views. In certain instances, details which are not necessaryfor an understanding of the present invention or which render otherdetails difficult to perceive may have been omitted.

Turning now to the drawing, and in particular to FIG. 1, there is showna top perspective view of a subframe according to the present invention,generally designated by reference numeral 1. The subframe 1 includes twocrossbeams 2 having ends to which frame elements 3 are coupled,respectively. Mounted to the frame elements 3 are bushings 4 by whichthe subframe 1 is linked to the motor vehicle axle, not shown.

FIG. 2 is an enlarged perspective view of the area encircled in FIG. 1,depicting the bushing 4 in greater detail. The bushing 4 is secured inthe frame element 3 via weld seams 5 in a formfitting manner and by amaterial joint.

FIG. 3 shows a top perspective view of the bushing 4 and it can be seenthat the bushing 4 includes a bushing body 6 and a face plate 7 which inturn has a contact surface 8. The face plate 7 is connected to thebushing body 6 via a circumferential weld seam 9. In relation to thevertical direction, indicated by arrow 10, the contact surface 8 israised relative to the busing body 6 and the weld seam 9, i.e. thecontact surface 8 is positioned at a vertical distance above the weldseam 9.

FIGS. 4 a, 4 b show cross sectional views of various embodiments of thebushing 4 according to the invention. According to FIG. 4 a, the faceplate 7 is realized as a formed part and has a depression 11 to therebyform the upwardly raised contact surface 8 in relation to a surface 12of the face plate 7. The contact surface 8 rests formfittingly at acontact point 13 of a vehicle body, only indicated here, and is securedby a threaded connection 14 which can be realized via a hollow space 15of the bushing body 6. Further indicated are the frame elements 13 whichare connected to the bushing body 6 by respective weld seams 5. The weldseam 9 is arranged below the contact surface 8, as viewed in thevertical direction 10, so that the contact surface 8 can be coupled withthe contact point 13 in a formfitting and very precise manner.

FIG. 4 b shows another embodiment of the bushing 4 in which the faceplate 7 has in cross section a U-shaped cup or pot-shaped part and alsoin this embodiment a contact surface 8 which contacts the contact point13 of the vehicle body in a formfitting manner. The pot-shaped part hasa bottom plate 16 and legs 17 extending from the bottom plate fromopposite ends. The ends of the legs 17 are welded by a weld seam 9 tothe confronting ends of the bushing body 6 so as to secure the faceplate 7 to the bushing body 6.

FIGS. 5 a, 5 b show two different cross sectional views of a bushing 4.FIG. 5 a shows one embodiment of a bushing 4 which is configured as apressed part having a bushing body 6 and a face plate 7, with the faceplate 7 being pressed into the bushing body 6. FIG. 5 b shows anotherembodiment of a bushing 4 which is configured as a flanged part, with abushing body 6 having flanged or bent ends 17 so that the face plate 7is coupled formfittingly. Common to both embodiments is the raisedposition of the contact surface 8 of the face plate 7 in relation to theend 18 of the bushing body 6.

While the invention has been illustrated and described in connectionwith currently preferred embodiments shown and described in detail, itis not intended to be limited to the details shown since variousmodifications and structural changes may be made without departing inany way from the spirit and scope of the present invention. Theembodiments were chosen and described in order to explain the principlesof the invention and practical application to thereby enable a personskilled in the art to best utilize the invention and various embodimentswith various modifications as are suited to the particular usecontemplated.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims and includes equivalents of theelements recited therein:

What is claimed is:
 1. A motor vehicle axle, comprising a subframehaving a bushing for linkage to a vehicle body, said bushing defining anaxis and including a bushing body and a face plate which is welded tothe bushing body at an upper end of the bushing body via a weld seam andhas a contact surface which is raised in relation to the weld seam, asviewed in a direction of the axis.
 2. The motor vehicle axle of claim 1,wherein the bushing body is configured in the form of a tube.
 3. Themotor vehicle axle of claim 2, wherein the tube has a round crosssection, or angular cross section, or oval cross section.
 4. The motorvehicle axle of claim 2, wherein the tube is longitudinally welded orclinched or roll formed or extruded.
 5. The motor vehicle axle of claim2, wherein the tube and the face plate are made of a material selectedfrom the group consisting of metal, steel, and light metal.
 6. The motorvehicle axle of claim 1, wherein the face plate has a depression,thereby forming the contact surface.
 7. The motor vehicle axle of claim1, wherein the face plate has a U-shaped cross section and defines abottom plate which forms the contact surface, and legs which extend fromthe bottom plate and are welded to the bushing body.
 8. A method,comprising welding ends of legs of a face plate to confronting ends of atubular body along a weld seam, such that a contact surface of the faceplate is raised in relation to the weld seam, as viewed in an axialdirection, thereby producing a bushing for linkage of a subframe for amotor vehicle axle to a vehicle body.
 9. The method of claim 8, furthercomprising recessing a bottom of the face plate between the legsoutwards to form the contact surface.
 10. The method of claim 8, whereinthe face plate is spot-welded to the bushing body.